My adviser told me to put off organic chem till junior year because I have not had enough bio. That sounds like BS, though. Do I really need upper level bio courses before orgo? I took gen chem this year.
O-chem is a very time intensive class. What are your grades like? Maybe your advisor thinks you still need some other college classes under your belt before you take a much harder class. (It isn't really that hard, the people who get screwed are those than don't keep up with the material... Learn good study habits now and they'll stick with you for the rest of your education....)
You should not wait. If anything take it in your soph year. At my undergrad, the program is designed so I can concurrently take gen bio III (evolution and ecology) and orgo. If there is one subject you may want to defer until junior year, it should be physics. But anyhow, I took them all soph year and got it over with and came out pretty well.
I would actually suggest the opposite, take organic before taking too many upperlevel bio courses. Depending on what bio you take it could be more difficult if you haven't had organic. I took cell and organic the same semester and in my cell class we were expected to know all the functional groups and some basic reactions. It was sort of confusing b/c I wouldn't learn the stuff in organic until about 2 weeks after I needed it for cell...
Most people at my school took organic I soph year and then waited until jr. year to take the second semester.